Evidence is building that fruit and vegetables play a vital role in good mental health, say Macquarie University researchers.
Young people should eat plenty of fruit and vegetables – but especially fruit – to lower their risk of depression, a new Macquarie University study suggests.
The association between higher fruit and vegetable consumption and preventing certain cancers and chronic illness such as heart disease is well known, and now the evidence is growing that fruit and veg may be just as key to good mental health.
“Depression is a real problem in Australia,” says study co-author, Associate Professor Seema Mihrshahi. “One in four young Australians have mental health issues – a really high proportion – so any kind of interventions to alleviate that are really important.”
Researchers in the Department of Health Systems and Populations at Macquarie reviewed the literature on the subject of fruit and vegetable consumption and depressive symptoms in people aged 15-45.
We know that very few people eat enough vegetables – only 1 in 20 are following the guidelines, whereas the figure is higher for fruit.
They found 12 cohort studies across Europe, the UK, US, Japan, Canada and Australia that followed people over time to investigate the association between their diet and mental health.
Most studies supported the evidence that eating enough fruit is associated with decreased risk of developing depression, the researchers found.
Fewer studies found an influence of vegetable consumption on depressive symptoms suggesting that there may be different effects of fruit and vegetables on mental health – although Dr Mihrshahi says it could also come down to the types of vegetables people commonly eat, and the fact that we just don’t eat enough of them.
Very low intakes of fruit and vegetables among young people generally was an important finding from all of the cohort studies, says Dr Mihrshahi, with intakes well below recommended guidelines.
The danger zone for young people
Australian guidelines recommend at least two servings of fruit a day and at least five of vegetables (half a cup of cooked vegies, or one cup of salad, constituting one serve).
The study’s lead author, Masters researcher in public health Putu Novi Arfirsta Dharmayani, says the research showed that healthy eating plummets in the age group that is most at risk of mental health problems.
“We found that there is a huge drop in fruit and vegetable consumption between the ages of 15 and 18, which is a very vulnerable group for mental health issues – the onset of depression symptoms is usually before the age of 20, during the transition to early adulthood,” Ms Dharmayani says.
Young Australians should increase their intake of fruit and vegetables and we hope these findings can help in advocating for increased consumption.
For more information: lighthouse.mq.edu.au